More than a dry spell

Even with late snows, water shortage likely in Taos region

Out of the past three years, 2018 has been the driest in the outset. While 92 percent of the state is at least "abnormally dry" (yellow, brown, orange), about 46 of New Mexico has moderate drought conditions (brown). Snowpack across the Rio Grande Basin reflects the lack of moisture — the measurement stands at only 4 percent of normal as of Jan. 1.

Map courtesy U.S. Drought Monitor

Posted
Thursday, January 11, 2018 4:55 pm

By Cody Hookschooks@taosnews.com

On a hillside in Taos Ski Valley is the Taos Powderhorn, a gauging station where scientists have for decades measured snow piling up in the Sangre de Cristo Mountains above the Taos Valley. In good years, the crystalline blanket is so thick and endless that a good agricultural season seems a no-brainer.

When a local scientist checked the station just after Christmas, rocks and bare ground stood out between sparse patches of snow.

A good growing season seemed like a fantastical stretch of the imagination. Even if late-spring snows do come in, it still probably will be a stretch.

As of Jan. 1, there was a mere five inches of snow at the Taos Powderhorn station, which will equate to little over an inch of water come spring. Across the state, the snowpack stood at a paltry 4 percent of normal. The snowpack in the entire Rio Grande Basin was only nine percent of normal.

At this time last year, the snowpack in the basin was 124 percent of normal.

Snowpack — the easiest to understand and most common measurement used to help predict New Mexico's water supply — is at a low not seen in two or three decades, depending on the location. This snow season is the slowest to start since 2000; the snow accumulation was similarly dismal in 2000, 2006 and 2013, according to data from the National Weather Service in Albuquerque.

“Pray for snow,” the refrain that’s been in vogue all winter, turned to hopeful anticipation as a major pressure system began to break apart this week; from Wednesday (Jan. 11) to Thursday, the storm is expected to drop a few inches of snow in the higher elevations in the mountains and a mix of rain and snow at lower elevations.

But scientists and water forecasters are not predicting New Mexico will make up the lack of early winter moisture.

“Water users and managers should anticipate shortfalls even this early in the water year,” according to the January water supply outlook prepared by the Natural Resources Conservation Service.

“New Mexicans are holding out that late winter snows will help the state catch up. Although possible, as we move further into January without measurable precipitation, let alone snow, the percentages of making up for lost time dwindle exponentially,” the report read.

The news of a dry year wasn’t unexpected as the La Niña weather phenomenon that sets up in the Pacific Ocean in the summer and autumn tends to heat up and dry out weather in the Southwest.

“It’s certainly dry, but this stretch is within the realm of historical variability,” said David Gutzler, a climatologist at the University of New Mexico in Albuquerque. “If there’s any single climatic factor pushing us in that [warm and dry] direction [this year], it’s La Niña,” he said.

But “looming in the background” and superimposed on La Niña conditions, he said, is the trend that’s been developing for the past few decades: the Southwest is getting warmer and drier. And with each passing year of those conditions, the models shift toward predicting more of them.

“We would not blame global warming for three months of no rain in New Mexico…but we expect to see the trend throughout the century,” Guztler said.

Still, the extent of the dryness is pronounced.

According to the Drought Monitor, a project of the University of Nebraska, about 93 percent of New Mexico is dry with about 46 percent of the state in moderate drought conditions — indicative of water shortages in some streams and wells. A year ago, just over 4 percent of New Mexico had drought conditions, according to the National Drought Mitigation Center.

It’s not only irrigators, big and small, who watch these measurements and predictions. So do the people charged with managing wildfires, which over the past decades have gotten bigger, costlier and more widespread.

Chuck Maxwell, a predictive meteorologist with the Southwest Coordination Center in Albuquerque, has been involved with wildland fires for 20 years. He’s seen winters like this “go either way” — that is, keep drying out or get the saving grace of significant moisture. “Very few times do we have a flat-out, dry and windy year from start to finish,” he said.

But it can be hard to tell. Snowpack, the tried and true measurement of his ilk of weather-watchers, has become less useful. As a predictor, “it started failing over and over again.”

Gutzler has found similar issues. “The connection between snowpack and streamflow is not as tight as it used to be. It's loosening as the climate warms up,” he said.

So now scientists like Maxwell and Gutzler have to use other measurements — of wind and temperature — to make their best guess for the coming year and the assuredly drier and warmer years to come.

Gutzler is part of a team with universities as far south as Juarez, Mexico that is spending five years developing a new model to understand the availability of water.

“Up and down the [Rio Grande] people are concerned about the water supply situation, both for this year and for long-term trends. The good news is we have good tools and models to give us some guidance about bad news,” he said. “The whole river’s connected. Ultimately, we’re all in the same boat.”